scholarly journals Soft X-Ray Spectroscopy from the X-Ray Polychromator on the Newly Repaired Solar Maximum Mission

1984 ◽  
Vol 86 ◽  
pp. 9-11
Author(s):  
K.T. Strong ◽  
R.A. Stern ◽  
J.R. Lemen ◽  
K.J.H. Phillips
Keyword(s):  
Spectroscopic Data ◽  
Solar Maximum ◽  
Active Regions ◽  
Line Profiles ◽  
Crystal Spectrometer ◽  
Solar Maximum Mission ◽  
X Ray ◽  
Bent Crystal ◽  
Mission Satellite ◽  
Short Presentation

The X-Ray Polychromator (XRP) resumed operations on 24 April 1984 following the successful in-orbit repair of the Solar Maximum Mission Satellite. Since that time the two instruments that comprise the XRP, the Flat Crystal Spectrometer (FCS) and the Bent Crystal Spectrometer (BCS), have been used to obtain new spectroscopic data from active regions and flares. The FCS, in particular, has accumulated far more observations of soft X-ray line profiles than were obtained during SMM-I in 1980. For this short presentation, we have chosen two topics to illustrate the type of data that we have obtained since the repair.

scholarly journals Distorted Wave Calculations: Application to Astrophysics and Tokamak Plasma

1984 ◽  
Vol 86 ◽  
pp. 92-99
Author(s):  
A.K. Bhatia
Keyword(s):  
Physical Properties ◽  
Spectral Resolution ◽  
Spectroscopic Data ◽  
Solar Maximum ◽  
Tokamak Plasma ◽  
Line Profiles ◽  
Distorted Wave ◽  
Solar Maximum Mission ◽  
X Ray ◽  
Line Intensities

During the last few years, observations of solar phenomena have been carried out by rocket flights, manned satellites like Skylab, unmanned satellites like Orbiting Solar Observatories and more recently Solar Maximum Mission. The wavelengths, line intensities and line profiles in UV and X-ray regions of the solar spectra have been measured. The spectroscopic data obtained are of high spatial and spectral resolution. The goal is to understand the physical properties of the emitting plasma and determine the electron temperatures, densities and volume of the emitting plasma from UV and X-ray spectra.

Time Variations of the Calcium Elemental Abundance in Flares from NOAA Active Regions 2562 and 2779

1988 ◽  
Vol 102 ◽  
pp. 189-193
Author(s):  
J. Sylwester ◽  
M.-C. Zolcinski-Couet ◽  
R.D. Bentley ◽  
J.R. Lemen
Keyword(s):  
Solar Maximum ◽  
Active Regions ◽  
Elemental Abundance ◽  
Crystal Spectrometer ◽  
Solar Maximum Mission ◽  
Bent Crystal ◽  
Time Variations ◽  
Abundance Variation ◽  
Future Work

AbstractAnalysis of flare spectra obtained with the Bent Crystal Spectrometer aboard the Solar Maximum Mission (SMM) satellite enables the determination of the fluxes in the resonance (w) line of Ca XIX and the near-by continuum. The line-to-continuum intensity ratio is a sensitive measure of the calcium elemental abundance (Aca) relative to hydrogen in the emitting plasma. In previous investigations we found the calcium abundance varies from flare to flare. In the present investigation we analyse the variations ofAcafor flares which occurred in two active regions well observed bySMM. We conclude that it is not possible to correlate the abundance variations with the time of the flare occurrence as suggested in an earlier paper for flares produced from a single active region. Further, we find no convincing correlation of abundance variation with any other flare characteristics. This negative result will stimulate future work on the physical interpretation of the calcium abundance variation.

scholarly journals Plasma Parameters and Structures of the X4 Flare of 19 May 1984 as Observed by SMM-XRP

1989 ◽  
Vol 104 (2) ◽  
pp. 165-168
Author(s):  
J.T. Schmelz ◽  
J.L.R. Saba ◽  
K.T. Strong
Keyword(s):  
Solar Maximum ◽  
Coronal Plasma ◽  
The Sun ◽  
Plasma Parameters ◽  
Crystal Spectrometer ◽  
Solar Maximum Mission ◽  
X Ray ◽  
Bent Crystal ◽  
East Limb ◽  
Large Flare

AbstractThe eruption of a large flare on the east limb of the Sun was observed by the X-Ray Polychromator (XRP) on board the Solar Maximum Mission (SMM) on 19 May 1984. The XRP Flat Crystal Spectrometer (FCS) made polychromatic soft X-ray images during the preflare, flare and postflare phases. The XRP Bent Crystal Spectrometer (BCS) provided information on the temperature and dynamics of the hot (Te > 8 x 106K) coronal plasma from spectra integrated spatially over the whole region.

scholarly journals New Results from the Solar Maximum Mission/Bent Crystal Spectrometer

Solar Physics ◽  
2017 ◽  
Vol 292 (4) ◽  
Author(s):  
C. G. Rapley ◽  
J. Sylwester ◽  
K. J. H. Phillips
Keyword(s):  
Solar Maximum ◽  
Crystal Spectrometer ◽  
Solar Maximum Mission ◽  
Bent Crystal

scholarly journals Spatially Resolved X-Ray Spectra of Coronal Active Regions

1975 ◽  
Vol 68 ◽  
pp. 67-67
Author(s):  
R. C. Catura ◽  
L. W. Acton ◽  
E. G. Joki ◽  
C. G. Rapley ◽  
J. L. Culhane
Keyword(s):  
Diffraction Pattern ◽  
Proportional Counter ◽  
Active Regions ◽  
Solar Image ◽  
Crystal Spectrometer ◽  
X Ray ◽  
Bent Crystal ◽  
Spatially Resolved ◽  
Position Sensitive ◽  
Multiple Spot

SummaryX-ray spectra from a number of coronal active regions were obtained during ATM support rocket flights carried out by the Lockheed group on June 11 and December 19, 1973. Multi-grid collimators were used to provide fields of view of 40″ diameter and 90″ diameter for a number of scanning crystal spectrometers and a bent crystal spectrometer which employed a position sensitive proportional counter to register the diffracted spectrum. A solar image was produced on film and on a TV camera on board the rocket with the aid of a 1 Å Hα filter. A small part of the X-ray collimator was used to generate a multiple spot diffraction pattern which was superimposed on the Hα image and the composite picture was transmitted to the ground. Pre-launch calibrations allowed the spot corresponding to the X-ray collimator axis to be identified and so the collimator pointing direction on the solar disc was controlled from the ground by means of commands sent to the rocket.

Observations from the Solar Maximum Mission

1991 ◽  
Vol 336 (1643) ◽  
pp. 327-337 ◽  
Keyword(s):  
Energy Release ◽  
Solar Maximum ◽  
Transport Processes ◽  
Crystal Spectrometer ◽  
Imaging Spectrometer ◽  
Holistic View ◽  
Solar Maximum Mission ◽  
Bent Crystal ◽  
X Ray Imaging ◽  
Ultraviolet Spectrometer

After nearly a decade of flare observations from the Solar Maximum Mission ( SMM ) the time has come to pause to review what has been accomplished and to identify the problems that remain to be solved. SMM has not only produced a comprehensive database on a variety of active-Sun phenomena but also taught us how to coordinate observations with ground-based observatories and other spacecraft to produce a more holistic view of the complex energy release and transport processes that we call a flare. SMM had a unique combination of four imaging instruments which emphasized the spectroscopy of the solar atmosphere. They were the Hard X-ray Imaging Spectrometer, the Bent Crystal Spectrometer, the Flat Crystal Spectrometer, and the Ultraviolet Spectrometer/Polarimeter. To illustrate the power of these instruments, this paper will describe the results of various studies of energy release, transport, and deposition phenomena during the onset of flares.

Solar flare X-ray spectra from the Solar Maximum Mission Flat Crystal Spectrometer

1982 ◽  
Vol 256 ◽  
pp. 774 ◽  
Author(s):  
K. J. H. Phillips ◽  
B. C. Fawcett ◽  
B. J. Kent ◽  
A. H. Gabriel ◽  
J. W. Leibacher ◽  
...  
Keyword(s):  
Solar Flare ◽  
Solar Maximum ◽  
Crystal Spectrometer ◽  
Solar Maximum Mission ◽  
X Ray

Variation of the Observed Coronal Calcium Abundance for Various X-Ray Flare Plasmas

1984 ◽  
Vol 86 ◽  
pp. 21-21
Author(s):  
J. Sylwester ◽  
J.R. Lemen ◽  
R. Mewe
Keyword(s):  
Solar Maximum ◽  
Elemental Abundance ◽  
Normalization Factor ◽  
Crystal Spectrometer ◽  
X Ray ◽  
Bent Crystal ◽  
Similar Temperature Dependence ◽  
Similar Temperature ◽  
Abundance Variation ◽  
The Continuum

We present the first observational evidence for the variation of the coronal calcium abundance in the high-temperature solar flare plasmas. The analyzed data consists of the X-ray flare spectra observed by the Solar Maximum Mission satellite with the Bent Crystal Spectrometer. From BCS spectra we derived the ratio of the line to continuum flux IL/IC for the resonance line of Ca XIX λ = 3.1781Å and the continuum at the same wavelength as a function of the temperature. The studies of 13 flares showed similar temperature dependence during the decay phases, but the agreement of the IL/IC ratio from flare to flare could only be achieved by adjusting an overall normalization factor. As the continuum flux depends weakly on the heavy elemental abundance, this variation of the IL/IC ratio can be attributed to the variation in the calcium abundance. For the flares considered, the variation between the extreme cases represented the factor of 2.5. We stress the consequences of the observed abundance variation for the analysis and interpretation of XUV and X-ray spectra.

scholarly journals Derivation of the Ionization Balance for Iron XIV/XXV and XXIII/XXIV Using Solar X-Ray Data

1984 ◽  
Vol 86 ◽  
pp. 13-16
Author(s):  
E. Antonucci ◽  
M.A. Dodero ◽  
A.H. Gabriel ◽  
K. Tanaka
Keyword(s):  
Solar Flares ◽  
Solar Maximum ◽  
Plasma Electron ◽  
Large Set ◽  
Spectral Emission ◽  
Crystal Spectrometer ◽  
X Ray ◽  
Physical Conditions ◽  
Bent Crystal ◽  
Ionization Balance

The relative concentrations of different ionization stages of iron are measured using the spectral emission of plasmas formed during solar flares. This is an extension of a study on the ionization balance of heavy elements, initiated with the analysis of calcium solar spectra (Antonucci et al., 1984). The data consist of a large set of iron spectra in the wavelength range from 1.84 to 1.88 Å, detected during the recent maximum of activity with the X-ray Polychromator Bent Crystal Spectrometer (BCS) on the NASA Solar Maximum Mission satellite and on the Soft X-ray Crystal Spectrometer (SOX) on the Hinotori satellite.At the low densities typical of the solar corona, in the steady state the ionization balance of an element is a function of the plasma electron temperature. Hence, it can be measured for plasmas of known temperature and in slowly varying physical conditions, and in most cases, solar flare plasmas can be considered to be in such conditions.

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